Method and apparatus for uplink transmissions in frame-based equipment nr unlicensed

ABSTRACT

Methods and apparatuses of a BSs and UEs in a wireless communication system are provided. A method of operating the UE comprises: receiving, from a BS over a shared spectrum channel, a first DCI including a COT of the BS; determining a first portion of the COT for a downlink transmission from the BS and a second portion of the COT for an uplink transmission to the BS, wherein the COT includes a gap between the first and second portions of the COT; performing a channel access procedure based on a duration of the gap; receiving the downlink transmission in the first portion of the COT; and transmitting the uplink transmission in the second portion of the COT based on a sensing status of the shared spectrum channel that is sensed as an idle state during the channel access procedure in the duration of the gap.

CROSS-REFERENCE TO RELATED APPLICATIONS AND CLAIM OF PRIORITY

This application is a continuation of U.S. patent application Ser. No.16/947,511, filed on Aug. 4, 2022, which claims priority to U.S.Provisional Patent Application No. 62/900,163, filed on Sep. 13, 2019and U.S. Provisional Patent Application No. 62/932,166, filed on Nov. 7,2019. The content of the above-identified patent documents isincorporated herein by reference.

TECHNICAL FIELD

The present application relates generally to wireless communicationsystems, more specifically, the present disclosure relates to uplinktransmission in frame-based equipment NR unlicensed.

BACKGROUND

A communication system includes a downlink (DL) that conveys signalsfrom transmission points such as base stations (BSs) or NodeBs to userequipments (UEs) and an uplink (UL) that conveys signals from UEs toreception points such as NodeBs. A UE, also commonly referred to as aterminal or a mobile station, may be fixed or mobile and may be acellular phone, a personal computer device, or an automated device. AneNodeB (eNB), referring to a NodeB in long-term evolution (LTE)communication system, and a gNodeB (gNB), referring to a NodeB in newradio (NR) communication system, may also be referred to as an accesspoint or other equivalent terminology.

SUMMARY

The present disclosure relates to a pre-5G or 5G communication system tobe provided for uplink transmission in frame-based equipment NRunlicensed.

In one embodiment, a user equipment (UE) in a wireless communicationsystem supporting a shared spectrum channel access is provided. The UEcomprises a transceiver configured to receive, from a base station (BS)over a shared spectrum channel, a first downlink control information(DCI) including a channel occupancy time (COT) of the BS. The UE furthercomprises a processor operably connected to the transceiver, theprocesser configured to: determine a first portion of the COT for adownlink transmission from the BS and a second portion of the COT for anuplink transmission to the BS, wherein the COT includes a gap betweenthe first and second portions of the COT; and perform a channel accessprocedure based on a duration of the gap. The transceiver of the UE isfurther configured to: receive, from the BS over the shared spectrumchannel, the downlink transmission in the first portion of the COT, andtransmit, to the BS over the shared spectrum channel, the uplinktransmission in the second portion of the COT, if the shared spectrumchannel is sensed as an idle state during the channel access procedurein the duration of the gap.

In another embodiment, a base station (BS) in a wireless communicationsystem supporting a shared spectrum channel access is provided. The BScomprises a processor configured to indicate a first portion of channeloccupancy time (COT) for a downlink transmission to a user equipment(UE) and a second portion of the COT for an uplink transmission from theUE, wherein the COT includes a gap between the first and second portionsof the COT. The BS further comprises a transceiver operably connected tothe processor, the transceiver configured to: transmit, to the UE over ashared spectrum channel, a first downlink control information (DCI)including the COT of the BS, transmit, to the UE over the sharedspectrum channel, the downlink transmission in the first portion of theCOT, and receive, from the UE over the shared spectrum channel, theuplink transmission in the second portion of the COT, if the sharedspectrum channel is sensed as an idle state during a channel accessprocedure that is performed based on a duration of the gap.

In yet another embodiment, a method of a user equipment (UE) in awireless communication system supporting a shared spectrum channelaccess is provided. The method comprises: receiving, from a base station(BS) over a shared spectrum channel, a first downlink controlinformation (DCI) including a channel occupancy time (COT) of the BS;and determining a first portion of the COT for a downlink transmissionfrom the BS and a second portion of the COT for an uplink transmissionto the BS, wherein the COT includes a gap between the first and secondportions of the COT; performing a channel access procedure based on aduration of the gap; receiving, from the BS over the shared spectrumchannel, the downlink transmission in the first portion of the COT; andtransmitting, to the BS over the shared spectrum channel, the uplinktransmission in the second portion of the COT based on a sensing statusof the shared spectrum channel that is sensed as an idle state duringthe channel access procedure in the duration of the gap.

Other technical features may be readily apparent to one skilled in theart from the following figures, descriptions, and claims.

Before undertaking the DETAILED DESCRIPTION below, it may beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document. The term “couple” and its derivativesrefer to any direct or indirect communication between two or moreelements, whether or not those elements are in physical contact with oneanother. The terms “transmit,” “receive,” and “communicate,” as well asderivatives thereof, encompass both direct and indirect communication.The terms “include” and “comprise,” as well as derivatives thereof, meaninclusion without limitation. The term “or” is inclusive, meaningand/or. The phrase “associated with,” as well as derivatives thereof,means to include, be included within, interconnect with, contain, becontained within, connect to or with, couple to or with, be communicablewith, cooperate with, interleave, juxtapose, be proximate to, be boundto or with, have, have a property of, have a relationship to or with, orthe like. The term “controller” means any device, system or part thereofthat controls at least one operation. Such a controller may beimplemented in hardware or a combination of hardware and software and/orfirmware. The functionality associated with any particular controllermay be centralized or distributed, whether locally or remotely. Thephrase “at least one of,” when used with a list of items, means thatdifferent combinations of one or more of the listed items may be used,and only one item in the list may be needed. For example, “at least oneof: A, B, and C” includes any of the following combinations: A, B, C, Aand B, A and C, B and C, and A and B and C.

Moreover, various functions described below can be implemented orsupported by one or more computer programs, each of which is formed fromcomputer readable program code and embodied in a computer readablemedium. The terms “application” and “program” refer to one or morecomputer programs, software components, sets of instructions,procedures, functions, objects, classes, instances, related data, or aportion thereof adapted for implementation in a suitable computerreadable program code. The phrase “computer readable program code”includes any type of computer code, including source code, object code,and executable code. The phrase “computer readable medium” includes anytype of medium capable of being accessed by a computer, such as readonly memory (ROM), random access memory (RAM), a hard disk drive, acompact disc (CD), a digital video disc (DVD), or any other type ofmemory. A “non-transitory” computer readable medium excludes wired,wireless, optical, or other communication links that transporttransitory electrical or other signals. A non-transitory computerreadable medium includes media where data can be permanently stored andmedia where data can be stored and later overwritten, such as arewritable optical disc or an erasable memory device.

Definitions for other certain words and phrases are provided throughoutthis patent document. Those of ordinary skill in the art shouldunderstand that in many if not most instances, such definitions apply toprior as well as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and itsadvantages, reference is now made to the following description taken inconjunction with the accompanying drawings, in which like referencenumerals represent like parts:

FIG. 1 illustrates an example wireless network according to embodimentsof the present disclosure;

FIG. 2 illustrates an example gNB according to embodiments of thepresent disclosure;

FIG. 3 illustrates an example UE according to embodiments of the presentdisclosure;

FIG. 4 illustrates an example transmitter structure using OFDM accordingto embodiments of the present disclosure;

FIG. 5 illustrates an example receiver structure using OFDM according toembodiments of the present disclosure;

FIG. 6 illustrates an example encoding process for a DCI formataccording to embodiments of the present disclosure;

FIG. 7 illustrates an example decoding process for a DCI format for usewith a UE according to embodiments of the present disclosure;

FIG. 8 illustrates an example timing for FBE operation according toembodiments of the present disclosure;

FIG. 9 illustrates an example LBT type for scheduled UL transmission inFBE NR-U according to embodiments of the present disclosure;

FIG. 10 illustrates another example LBT type for scheduled ULtransmission in FBE NR-U according to embodiments of the presentdisclosure;

FIG. 11 illustrates yet another example LBT type for scheduled ULtransmission in FBE NR-U according to embodiments of the presentdisclosure;

FIG. 12 illustrates yet another example LBT type for scheduled ULtransmission in FBE NR-U according to embodiments of the presentdisclosure;

FIG. 13 illustrates yet another example LBT type for scheduled ULtransmission in FBE NR-U according to embodiments of the presentdisclosure;

FIG. 14 illustrates an example CG-PUSCH for an FBE UE according toembodiments of the present disclosure;

FIG. 15 illustrates another example CG-PUSCH for an FBE UE according toembodiments of the present disclosure;

FIG. 16 illustrates yet another example CG-PUSCH for an FBE UE accordingto embodiments of the present disclosure;

FIG. 17 illustrates yet another example CG-PUSCH for an FBE UE accordingto embodiments of the present disclosure;

FIG. 18 illustrates yet another example CG-PUSCH for an FBE UE accordingto embodiments of the present disclosure;

FIG. 19 illustrates an example RO for an FBE UE according to embodimentsof the present disclosure; and

FIG. 20 illustrates a flow chart of a method for uplink transmission inframe-based equipment NR unlicensed according to embodiments of thepresent disclosure.

DETAILED DESCRIPTION

FIG. 1 through FIG. 20 , discussed below, and the various embodimentsused to describe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged system or device.

The following documents are hereby incorporated by reference into thepresent disclosure as if fully set forth herein: 3GPP TS 38.211 v15.4.0,“NR; Physical channels and modulation;” 3GPP TS 38.212 v15.4.0, “NR;Multiplexing and Channel coding;” 3GPP TS 38.213 v15.4.0, “NR; PhysicalLayer Procedures for Control;” 3GPP TS 38.214 v15.4.0, “NR; PhysicalLayer Procedures for Data;” 3GPP TS 38.331 v15.4.0, “NR; Radio ResourceControl (RRC) Protocol Specification;” ETSI EN 301 893 V2.1.1, “5 GHzRLAN; Harmonised Standard covering the essential requirements of article3.2 of Directive 2014/53/EU”, 2017; ETSI EN 302 567 V2.1.1,“Multiple-Gigabit/s radio equipment operating in the 60 GHz band;Harmonised Standard covering the essential requirements of article 3.2of Directive 2014/53/EU”, 2017; 3GPP TR 36.889 V13.0.0, “Study onLicensed-Assisted Access to Unlicensed Spectrum”, 2015; and IEEE Std802.11-2016, “Part 11: Wireless LAN Medium Access Control (MAC) andPhysical Layer (PHY) Specifications”, 2016.

FIGS. 1-3 below describe various embodiments implemented in wirelesscommunications systems and with the use of orthogonal frequency divisionmultiplexing (OFDM) or orthogonal frequency division multiple access(OFDMA) communication techniques. The descriptions of FIGS. 1-3 are notmeant to imply physical or architectural limitations to the manner inwhich different embodiments may be implemented. Different embodiments ofthe present disclosure may be implemented in any suitably arrangedcommunications system.

FIG. 1 illustrates an example wireless network according to embodimentsof the present disclosure. The embodiment of the wireless network shownin FIG. 1 is for illustration only. Other embodiments of the wirelessnetwork 100 could be used without departing from the scope of thepresent disclosure.

As shown in FIG. 1 , the wireless network includes a gNB 101, a gNB 102,and a gNB 103. The gNB 101 communicates with the gNB 102 and the gNB103. The gNB 101 also communicates with at least one network 130, suchas the Internet, a proprietary Internet Protocol (IP) network, or otherdata network.

The gNB 102 provides wireless broadband access to the network 130 for afirst plurality of user equipments (UEs) within a coverage area 120 ofthe gNB 102. The first plurality of UEs includes a UE 111, which may belocated in a small business (SB); a UE 112, which may be located in anenterprise (E); a UE 113, which may be located in a WiFi hotspot (HS); aUE 114, which may be located in a first residence (R); a UE 115, whichmay be located in a second residence (R); and a UE 116, which may be amobile device (M), such as a cell phone, a wireless laptop, a wirelessPDA, or the like. The gNB 103 provides wireless broadband access to thenetwork 130 for a second plurality of UEs within a coverage area 125 ofthe gNB 103. The second plurality of UEs includes the UE 115 and the UE116. In some embodiments, one or more of the gNBs 101-103 maycommunicate with each other and with the UEs 111-116 using 5G, LTE,LTE-A, WiMAX, WiFi, or other wireless communication techniques.

Depending on the network type, the term “base station” or “BS” can referto any component (or collection of components) configured to providewireless access to a network, such as transmit point (TP),transmit-receive point (TRP), an enhanced base station (eNodeB or eNB),a 5G base station (gNB), a macrocell, a femtocell, a WiFi access point(AP), or other wirelessly enabled devices. Base stations may providewireless access in accordance with one or more wireless communicationprotocols, e.g., 5G 3GPP new radio interface/access (NR), long termevolution (LTE), LTE advanced (LTE-A), high speed packet access (HSPA),Wi-Fi 802.11a/b/g/n/ac, etc. For the sake of convenience, the terms “BS”and “TRP” are used interchangeably in this patent document to refer tonetwork infrastructure components that provide wireless access to remoteterminals. Also, depending on the network type, the term “userequipment” or “UE” can refer to any component such as “mobile station,”“subscriber station,” “remote terminal,” “wireless terminal,” “receivepoint,” or “user device.” For the sake of convenience, the terms “userequipment” and “UE” are used in this patent document to refer to remotewireless equipment that wirelessly accesses a BS, whether the UE is amobile device (such as a mobile telephone or smartphone) or is normallyconsidered a stationary device (such as a desktop computer or vendingmachine).

Dotted lines show the approximate extents of the coverage areas 120 and125, which are shown as approximately circular for the purposes ofillustration and explanation only. It should be clearly understood thatthe coverage areas associated with gNBs, such as the coverage areas 120and 125, may have other shapes, including irregular shapes, dependingupon the configuration of the gNBs and variations in the radioenvironment associated with natural and man-made obstructions.

As described in more detail below, one or more of the UEs 111-116include circuitry, programing, or a combination thereof, for uplinktransmissions in frame-based equipment in NR unlicensed. In certainembodiments, and one or more of the gNBs 101-103 includes circuitry,programing, or a combination thereof, for efficient uplink transmissionin frame-based equipment NR unlicensed.

Although FIG. 1 illustrates one example of a wireless network, variouschanges may be made to FIG. 1 . For example, the wireless network couldinclude any number of gNBs and any number of UEs in any suitablearrangement. Also, the gNB 101 could communicate directly with anynumber of UEs and provide those UEs with wireless broadband access tothe network 130. Similarly, each gNB 102-103 could communicate directlywith the network 130 and provide UEs with direct wireless broadbandaccess to the network 130. Further, the gNBs 101, 102, and/or 103 couldprovide access to other or additional external networks, such asexternal telephone networks or other types of data networks.

FIG. 2 illustrates an example gNB 102 according to embodiments of thepresent disclosure. The embodiment of the gNB 102 illustrated in FIG. 2is for illustration only, and the gNBs 101 and 103 of FIG. 1 could havethe same or similar configuration. However, gNBs come in a wide varietyof configurations, and FIG. 2 does not limit the scope of the presentdisclosure to any particular implementation of a gNB.

As shown in FIG. 2 , the gNB 102 includes multiple antennas 205 a-205 n,multiple RF transceivers 210 a-210 n, transmit (TX) processing circuitry215, and receive (RX) processing circuitry 220. The gNB 102 alsoincludes a controller/processor 225, a memory 230, and a backhaul ornetwork interface 235.

The RF transceivers 210 a-210 n receive, from the antennas 205 a-205 n,incoming RF signals, such as signals transmitted by UEs in the network100. The RF transceivers 210 a-210 n down-convert the incoming RFsignals to generate IF or baseband signals. The IF or baseband signalsare sent to the RX processing circuitry 220, which generates processedbaseband signals by filtering, decoding, and/or digitizing the basebandor IF signals. The RX processing circuitry 220 transmits the processedbaseband signals to the controller/processor 225 for further processing.

The TX processing circuitry 215 receives analog or digital data (such asvoice data, web data, e-mail, or interactive video game data) from thecontroller/processor 225. The TX processing circuitry 215 encodes,multiplexes, and/or digitizes the outgoing baseband data to generateprocessed baseband or IF signals. The RF transceivers 210 a-210 nreceive the outgoing processed baseband or IF signals from the TXprocessing circuitry 215 and up-converts the baseband or IF signals toRF signals that are transmitted via the antennas 205 a-205 n.

The controller/processor 225 can include one or more processors or otherprocessing devices that control the overall operation of the gNB 102.For example, the controller/processor 225 could control the reception offorward channel signals and the transmission of reverse channel signalsby the RF transceivers 210 a-210 n, the RX processing circuitry 220, andthe TX processing circuitry 215 in accordance with well-knownprinciples. The controller/processor 225 could support additionalfunctions as well, such as more advanced wireless communicationfunctions. For instance, the controller/processor 225 could support beamforming or directional routing operations in which outgoing signals frommultiple antennas 205 a-205 n are weighted differently to effectivelysteer the outgoing signals in a desired direction. Any of a wide varietyof other functions could be supported in the gNB 102 by thecontroller/processor 225.

The controller/processor 225 is also capable of executing programs andother processes resident in the memory 230, such as an OS. Thecontroller/processor 225 can move data into or out of the memory 230 asrequired by an executing process.

The controller/processor 225 is also coupled to the backhaul or networkinterface 235. The backhaul or network interface 235 allows the gNB 102to communicate with other devices or systems over a backhaul connectionor over a network. The interface 235 could support communications overany suitable wired or wireless connection(s). For example, when the gNB102 is implemented as part of a cellular communication system (such asone supporting 5G, LTE, or LTE-A), the interface 235 could allow the gNB102 to communicate with other gNBs over a wired or wireless backhaulconnection. When the gNB 102 is implemented as an access point, theinterface 235 could allow the gNB 102 to communicate over a wired orwireless local area network or over a wired or wireless connection to alarger network (such as the Internet). The interface 235 includes anysuitable structure supporting communications over a wired or wirelessconnection, such as an Ethernet or RF transceiver.

The memory 230 is coupled to the controller/processor 225. Part of thememory 230 could include a RAM, and another part of the memory 230 couldinclude a Flash memory or other ROM.

Although FIG. 2 illustrates one example of the gNB 102, various changesmay be made to FIG. 2 . For example, the gNB 102 could include anynumber of each component shown in FIG. 2 . As a particular example, anaccess point could include a number of interfaces 235, and thecontroller/processor 225 could support routing functions to route databetween different network addresses. As another particular example,while shown as including a single instance of TX processing circuitry215 and a single instance of RX processing circuitry 220, the gNB 102could include multiple instances of each (such as one per RFtransceiver). Also, various components in FIG. 2 could be combined,further subdivided, or omitted and additional components could be addedaccording to particular needs.

FIG. 3 illustrates an example UE 116 according to embodiments of thepresent disclosure. The embodiment of the UE 116 illustrated in FIG. 3is for illustration only, and the UEs 111-115 of FIG. 1 could have thesame or similar configuration. However, UEs come in a wide variety ofconfigurations, and FIG. 3 does not limit the scope of the presentdisclosure to any particular implementation of a UE.

As shown in FIG. 3 , the UE 116 includes an antenna 305, a radiofrequency (RF) transceiver 310, TX processing circuitry 315, amicrophone 320, and receive (RX) processing circuitry 325. The UE 116also includes a speaker 330, a processor 340, an input/output (I/O)interface (IF) 345, a touchscreen 350, a display 355, and a memory 360.The memory 360 includes an operating system (OS) 361 and one or moreapplications 362.

The RF transceiver 310 receives, from the antenna 305, an incoming RFsignal transmitted by a gNB of the network 100. The RF transceiver 310down-converts the incoming RF signal to generate an intermediatefrequency (IF) or baseband signal. The IF or baseband signal is sent tothe RX processing circuitry 325, which generates a processed basebandsignal by filtering, decoding, and/or digitizing the baseband or IFsignal. The RX processing circuitry 325 transmits the processed basebandsignal to the speaker 330 (such as for voice data) or to the processor340 for further processing (such as for web browsing data).

The TX processing circuitry 315 receives analog or digital voice datafrom the microphone 320 or other outgoing baseband data (such as webdata, e-mail, or interactive video game data) from the processor 340.The TX processing circuitry 315 encodes, multiplexes, and/or digitizesthe outgoing baseband data to generate a processed baseband or IFsignal. The RF transceiver 310 receives the outgoing processed basebandor IF signal from the TX processing circuitry 315 and up-converts thebaseband or IF signal to an RF signal that is transmitted via theantenna 305.

The processor 340 can include one or more processors or other processingdevices and execute the OS 361 stored in the memory 360 in order tocontrol the overall operation of the UE 116. For example, the processor340 could control the reception of forward channel signals and thetransmission of reverse channel signals by the RF transceiver 310, theRX processing circuitry 325, and the TX processing circuitry 315 inaccordance with well-known principles. In some embodiments, theprocessor 340 includes at least one microprocessor or microcontroller.

The processor 340 is also capable of executing other processes andprograms resident in the memory 360, such as processes for beammanagement. The processor 340 can move data into or out of the memory360 as required by an executing process. In some embodiments, theprocessor 340 is configured to execute the applications 362 based on theOS 361 or in response to signals received from gNBs or an operator. Theprocessor 340 is also coupled to the I/O interface 345, which providesthe UE 116 with the ability to connect to other devices, such as laptopcomputers and handheld computers. The I/O interface 345 is thecommunication path between these accessories and the processor 340.

The processor 340 is also coupled to the touchscreen 350 and the display355. The operator of the UE 116 can use the touchscreen 350 to enterdata into the UE 116. The display 355 may be a liquid crystal display,light emitting diode display, or other display capable of rendering textand/or at least limited graphics, such as from web sites.

The memory 360 is coupled to the processor 340. Part of the memory 360could include a random-access memory (RAM), and another part of thememory 360 could include a Flash memory or other read-only memory (ROM).

Although FIG. 3 illustrates one example of the UE 116, various changesmay be made to FIG. 3 . For example, various components in FIG. 3 couldbe combined, further subdivided, or omitted and additional componentscould be added according to particular needs. As a particular example,the processor 340 could be divided into multiple processors, such as oneor more central processing units (CPUs) and one or more graphicsprocessing units (GPUs). Also, while FIG. 3 illustrates the UE 116configured as a mobile telephone or smartphone, UEs could be configuredto operate as other types of mobile or stationary devices.

The present disclosure relates generally to wireless communicationsystems and, more specifically, to reducing power consumption for a userequipment (UE) communicating with a base station and to transmissions toand receptions from a UE of physical downlink control channels (PDCCHs)for operation with dual connectivity. A communication system includes adownlink (DL) that refers to transmissions from a base station or one ormore transmission points to UEs and an uplink (UL) that refers totransmissions from UEs to a base station or to one or more receptionpoints.

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems, efforts have been made todevelop an improved 5G or pre-5G communication system. Therefore, the 5Gor pre-5G communication system is also called a “beyond 4G network” or a“post LTE system.” The 5G communication system is considered to beimplemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, soas to accomplish higher data rates. To decrease propagation loss of theradio waves and increase the transmission distance, the beamforming,massive multiple-input multiple-output (MIMO), full dimensional MIMO(FD-MIMO), array antenna, an analog beam forming, large scale antennatechniques are discussed in 5G communication systems. In addition, in 5Gcommunication systems, development for system network improvement isunder way based on advanced small cells, cloud radio access networks(RANs), ultra-dense networks, device-to-device (D2D) communication,wireless backhaul, moving network, cooperative communication,coordinated multi-points (CoMP), reception-end interference cancellationand the like.

A time unit for DL signaling or for UL signaling on a cell is referredto as a slot and can include one or more symbols. A symbol can alsoserve as an additional time unit. A frequency (or bandwidth (BW)) unitis referred to as a resource block (RB). One RB includes a number ofsub-carriers (SCs). For example, a slot can include 14 symbols, haveduration of 1 millisecond or 0.5 milliseconds, and an RB can have a BWof 180 kHz or 360 kHz and include 12 SCs with inter-SC spacing of 15 kHzor 30 kHz, respectively.

DL signals include data signals conveying information content, controlsignals conveying DL control information (DCI) formats, and referencesignals (RS) that are also known as pilot signals. A gNB can transmitdata information (e.g., transport blocks) or DCI formats throughrespective physical DL shared channels (PDSCHs) or physical DL controlchannels (PDCCHs). A gNB can transmit one or more of multiple types ofRS including channel state information RS (CSI-RS) and demodulation RS(DMRS). A CSI-RS is intended for UEs to measure channel stateinformation (CSI) or to perform other measurements such as ones relatedto mobility support. A DMRS can be transmitted only in the BW of arespective PDCCH or PDSCH and a UE can use the DMRS to demodulate dataor control information.

UL signals also include data signals conveying information content,control signals conveying UL control information (UCI), and RS. A UEtransmits data information (e.g., transport blocks) or UCI through arespective physical UL shared channel (PUSCH) or a physical UL controlchannel (PUCCH). When a UE simultaneously transmits data information andUCI, the UE can multiplex both in a PUSCH or transmit them separately inrespective PUSCH and PUCCH. UCI includes hybrid automatic repeat requestacknowledgement (HARQ-ACK) information, indicating correct or incorrectdetection of data transport blocks (TBs) by a UE, scheduling request(SR) indicating whether a UE has data in the UE's buffer, and CSIreports enabling a gNB to select appropriate parameters to perform linkadaptation for PDSCH or PDCCH transmissions to a UE.

A CSI report from a UE can include a channel quality indicator (CQI)informing a gNB of a modulation and coding scheme (MCS) for the UE todetect a data TB with a predetermined block error rate (BLER), such as a10% BLER, of a precoding matrix indicator (PMI) informing a gNB how toprecode signaling to a UE, and of a rank indicator (RI) indicating atransmission rank for a PDSCH. UL RS includes DMRS and sounding RS(SRS). DMRS is transmitted only in a BW of a respective PUSCH or PUCCHtransmission. A gNB can use a DMRS to demodulate information in arespective PUSCH or PUCCH. SRS is transmitted by a UE to provide a gNBwith UL CSI and, for a TDD or a flexible duplex system, to also providea PMI for DL transmissions. An UL DMRS or SRS transmission can be based,for example, on a transmission of a Zadoff-Chu (ZC) sequence or, ingeneral, of a CAZAC sequence.

DL transmissions and UL transmissions can be based on an orthogonalfrequency division multiplexing (OFDM) waveform including a variantusing DFT precoding that is known as DFT-spread-OFDM.

FIG. 4 illustrates an example transmitter structure 400 using OFDMaccording to embodiments of the present disclosure. An embodiment of thetransmitter structure 400 shown in FIG. 4 is for illustration only. Oneor more of the components illustrated in FIG. 4 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

Information bits, such as DCI bits or data bits 410, are encoded byencoder 420, rate matched to assigned time/frequency resources by ratematcher 430 and modulated by modulator 440. Subsequently, modulatedencoded symbols and DMRS or CSI-RS 450 are mapped to SCs 460 by SCmapping unit 465, an inverse fast Fourier transform (IFFT) is performedby filter 470, a cyclic prefix (CP) is added by CP insertion unit 480,and a resulting signal is filtered by filter 490 and transmitted by aradio frequency (RF) unit 495.

FIG. 5 illustrates an example receiver structure 500 using OFDMaccording to embodiments of the present disclosure. An embodiment of thereceiver structure 500 shown in FIG. 5 is for illustration only. One ormore of the components illustrated in FIG. 8 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

A received signal 510 is filtered by filter 520, a CP removal unitremoves a CP 530, a filter 540 applies a fast Fourier transform (FFT),SCs de-mapping unit 550 de-maps SCs selected by BW selector unit 555,received symbols are demodulated by a channel estimator and ademodulator unit 560, a rate de-matcher 570 restores a rate matching,and a decoder 580 decodes the resulting bits to provide information bits590.

A UE typically monitors multiple candidate locations for respectivepotential PDCCH transmissions to decode multiple candidate DCI formatsin a slot. Monitoring a PDCCH candidates means receiving and decodingthe PDCCH candidate according to DCI formats the UE is configured toreceive. A DCI format includes cyclic redundancy check (CRC) bits inorder for the UE to confirm a correct detection of the DCI format. A DCIformat type is identified by a radio network temporary identifier (RNTI)that scrambles the CRC bits. For a DCI format scheduling a PDSCH or aPUSCH to a single UE, the RNTI can be a cell RNTI (C-RNTI) and serves asa UE identifier.

For a DCI format scheduling a PDSCH conveying system information (SI),the RNTI can be an SI-RNTI. For a DCI format scheduling a PDSCHproviding a random-access response (RAR), the RNTI can be an RA-RNTI.For a DCI format scheduling a PDSCH or a PUSCH to a single UE prior to aUE establishing a radio resource control (RRC) connection with a servinggNB, the RNTI can be a temporary C-RNTI (TC-RNTI). For a DCI formatproviding TPC commands to a group of UEs, the RNTI can be aTPC-PUSCH-RNTI or a TPC-PUCCH-RNTI. Each RNTI type can be configured toa UE through higher layer signaling such as RRC signaling. A DCI formatscheduling PDSCH transmission to a UE is also referred to as DL DCIformat or DL assignment while a DCI format scheduling PUSCH transmissionfrom a UE is also referred to as UL DCI format or UL grant.

A PDCCH transmission can be within a set of physical RBs (PRBs). A gNBcan configure a UE one or more sets of PRBs, also referred to as controlresource sets, for PDCCH receptions. A PDCCH transmission can be incontrol channel elements (CCEs) that are included in a control resourceset. A UE determines CCEs for a PDCCH reception based on a search spacesuch as a UE-specific search space (USS) for PDCCH candidates with DCIformat having CRC scrambled by a RNTI, such as a C-RNTI, that isconfigured to the UE by UE-specific RRC signaling for scheduling PDSCHreception or PUSCH transmission, and a common search space (CSS) forPDCCH candidates with DCI formats having CRC scrambled by other RNTIs. Aset of CCEs that can be used for PDCCH transmission to a UE define aPDCCH candidate location. A property of a control resource set istransmission configuration indication (TCI) state that provides quasico-location information of the DMRS antenna port for PDCCH reception.

FIG. 6 illustrates an example encoding process 600 for a DCI formataccording to embodiments of the present disclosure. An embodiment of theencoding process 600 shown in FIG. 6 is for illustration only. One ormore of the components illustrated in FIG. 6 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

A gNB separately encodes and transmits each DCI format in a respectivePDCCH. A RNTI masks a CRC of the DCI format codeword in order to enablethe UE to identify the DCI format. For example, the CRC and the RNTI caninclude, for example, 16 bits or 24 bits. The CRC of (non-coded) DCIformat bits 610 is determined using a CRC computation unit 620, and theCRC is masked using an exclusive OR (XOR) operation unit 630 between CRCbits and RNTI bits 640. The XOR operation is defined as XOR (0, 0)=0,XOR (0, 1)=1, XOR (1, 0)=1, XOR (1, 1)=0. The masked CRC bits areappended to DCI format information bits using a CRC append unit 650. Anencoder 660 performs channel coding (such as tail-biting convolutionalcoding or polar coding), followed by rate matching to allocatedresources by rate matcher 670. Interleaving and modulation units 680apply interleaving and modulation, such as QPSK, and the output controlsignal 690 is transmitted.

FIG. 7 illustrates an example decoding process 700 for a DCI format foruse with a UE according to embodiments of the present disclosure. Anembodiment of the decoding process 700 shown in FIG. 7 is forillustration only. One or more of the components illustrated in FIG. 7can be implemented in specialized circuitry configured to perform thenoted functions or one or more of the components can be implemented byone or more processors executing instructions to perform the notedfunctions. Other embodiments are used without departing from the scopeof the present disclosure.

A received control signal 710 is demodulated and de-interleaved by ademodulator and a de-interleaver 720. A rate matching applied at a gNBtransmitter is restored by rate matcher 730, and resulting bits aredecoded by decoder 740. After decoding, a CRC extractor 750 extracts CRCbits and provides DCI format information bits 760. The DCI formatinformation bits are de-masked 770 by an XOR operation with an RNTI 780(when applicable) and a CRC check is performed by unit 790. When the CRCcheck succeeds (checksum is zero), the DCI format information bits areconsidered to be valid. When the CRC check does not succeed, the DCIformat information bits are considered to be invalid.

A frame based equipment (FBE) is a channel access mechanism wherein thetransmit/receive structure has a periodic timing with a periodicitynamed the fixed frame period (FFP); and that the initiating device mayperform listen-before-talk (LBT) during an observation slot beforestarting transmissions on an operating channel at the start of a FFP.The FFP is within 1 ms to 10 ms, and the observation slot is at least 9microseconds. If the LBT fails on an operating channel, the initiatingdevice may not transmit on that channel, except for short controlsignaling transmissions providing it complies with certain requirements.The channel occupancy time (COT) associated with a successful LBT checkfor FBE operation may be no greater than 95% of the FFP, and may befollowed by an idle period until the start of next FFP such that theidle period is at least the max(5% of channel occupancy time, 100microseconds).

FIG. 8 illustrates an example timing for FBE operation 800 according toembodiments of the present disclosure. An embodiment of the timing forFBE operation 800 shown in FIG. 8 is for illustration only. One or moreof the components illustrated in FIG. 8 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

In the present disclosure, an observation slot refers to the durationfor an FBE device to perform LBT, while an NR-U slot refers to a slot of14 OFDM symbols of the NR-U system.

Besides the load-based equipment (LBE) operation mode, NR unlicensed(NR-U) can also support the above FBE operation mode for variousapplication scenarios. Examples can include a single NR-U operatorexists in the operating channel(s) and other Wi-Fi network can beprecluded (e.g., by deployment); and two or more NR-U operators coexistin the operating channel(s), potentially with coordination among theoperators; and one or more NR-U operator coexist with an FBE operationbased Wi-Fi network; etc. Compared to the LBE operation mode, the FBEoperation mode can potentially have higher spectrum utilization undersuch scenarios, given the much simpler LBT process in FBE operation thanthe ones in LBE operation.

The present disclosure focuses on the enhancements of Rel-15 NR tosupport uplink transmissions for FBE NR-U, which includes enhancementsto scheduled UL transmission for FBE NR-U, enhancements to configuredgrant UL transmissions for FBE NR-U, and enhancements to PRACHtransmissions for FBE NR-U.

The present disclosure includes several embodiments, principles,approaches and examples that can be used in conjunction or incombination with one another, or can operate as standalone. Theembodiments/principles/approaches/examples in this disclosure can beapplied to FBE-based NR-U, LBE-based NR-U, or both FBE-based andLBE-based NR-U.

In the present disclosure, FR1 NR-U refers to NR-U that operates in theunlicensed/shared bands in FR1, such as the 5 GHz unlicensed bands orthe 6 GHz unlicensed/shared bands; and FR2 GHz NR-U refers to NR-U thatoperators in the unlicensed/shared bands in FR2, such as the 60 GHzunlicensed bands.

The present disclosure focuses on the enhancements of Rel-15 NR tosupport uplink transmissions for FBE NR-U, which includes enhancementsto scheduled UL transmission for FBE NR-U, enhancements to configuredgrant UL transmissions for FBE NR-U, and enhancements to PRACHtransmissions for FBE NR-U.

In one embodiment, the signaling and indication methods are provided tosupport PUSCH transmissions scheduled by UL grant for FBE NR-U.

In one embodiment, the general LBT type for granting UL transmissionsfor NR-U can include: CAT-4 LBT, wherein each CAT-4 LBT type can have acorresponding LBT priority class value. For example, there can be atotal of 4 LBT priority class values, and the lower the priority classvalue, the higher the channel access priority. The CAT-4 LBT can be usedby the UE to obtain a UE-initiated COT; CAT-2 LBT of T μs duration,where 16<=T<=25. This can be used when the gap from the start of the ULtransmission to the end of previous transmission is at least 16 μs, andthe CAT-2 LBT is successful if the energy detected on the operatingchannel during a single observation slot or two observation slots withinthe T μs duration is below the energy detection threshold; and CAT-1 LBTwith immediate transmission. This can be used when the gap from thestart of the UL transmission to the end of previous transmission is lessthan 16 μs.

In one embodiment, the LBT type for UL transmission in FBE NR-U caninclude CAT-2 LBT and CAT-1 LBT and does not include CAT-4 LBT.

In one example, the CAT-2 LBT for UL transmission in FBE NR-U caninclude only 1 type. In one sub-example, a successful CAT-2 LBT can bereferred to the operating channel during a single observation slotwithin a 25 μs duration ending immediately before the start of the ULtransmission is below the energy detection threshold. In anothersub-example, a successful CAT-2 LBT can be referred to the operatingchannel during two observation slots within a 25 μs duration endingimmediately before the start of the UL transmission are both below theenergy detection threshold.

In one example, the CAT-2 LBT for UL transmission in FBE NR-U caninclude 2 types, with one type being CAT-2 LBT of 16 μs duration and theother type being CAT-2 LBT of 25 μs duration. In one sub-example, asuccessful CAT-2 LBT of 16 μs can be referred to the operating channelduring a single observation slot or two observation slots within a 16 μsduration ending immediately before the start of the UL transmission isbelow the energy detection threshold. In another sub-example, asuccessful CAT-2 LBT of 25 μs can be referred to the operating channelduring a single observation slot or two observation slots within a 25 μsduration ending immediately before the start of the UL transmission arebelow the energy detection threshold.

In one example, the CAT-4 LBT and correspondingly the LBT priority classvalue for CAT-4 LBT do not need to be indicated for UL transmissions inFBE NR-U.

In one example, the LBT type for scheduled UL transmission in FBE NR-Ucan be explicitly indicated through the UL grant that schedules the ULtransmissions.

In one example, the UL grant can have an LBT type field to indicate oneof the CAT-1 LBT or CAT-2 LBT. In one sub-example, the number of bitsfor the LBT type field in the UL grant requires 1 bit. In anothersub-example, the CAT-2 LBT can refer to the CAT-2 LBT type as in thementioned embodiments and/or examples. In another sub-example, the CAT-2LBT can refer to one of the CAT-2 LBT of 16 μs or CAT-2 LBT of 25 μs,wherein the higher layer parameter (e.g., RRC parameter) can configureone of the CAT-2 LBT of 16 μs or CAT-2 LBT of 25 μs to be indicated bythe UL grant. In yet another sub-example, the CAT-2 LBT can refer to oneof the CAT-2 LBT of 16 μs or CAT-2 LBT of 25 μs, which can be fixed inthe specification. In yet another sub-example, CAT-1 LBT can bescheduled by the gNB if the end of the previous transmission within thefixed frame period (FFP) and the start of the scheduled UL transmissionis at most 16 μs.

In one example, the UL grant can have an LBT type field to indicate oneof the CAT-1 LBT, CAT-2 LBT of 16 μs, and CAT-2 LBT of 25 μs. In onesub-example, the number of bits for the LBT type field in the UL grantrequires 2 bits. In another sub-example, the CAT-2 LBT of 16 μs, andCAT-2 LBT of 25 μs can refer to the CAT-2 LBT type as in the mentionedembodiments and/or examples.

In one example, the starting and length indicator value (SLIV) indicatedin the UL grant for the scheduled UL transmission can be interpreted asthe starting symbol for the LBT operation before the scheduled ULtransmission, and the UL transmission can start after the LBT operationis finished. In one sub-example, the UL transmission may be punctured inthe first symbol after the LBT operation.

In one example, the starting and length indicator value (SLIV) indicatedin the UL grant for the scheduled UL transmission can be interpreted asthe starting symbol for the scheduled UL transmission, and the LBToperation is performed before the indicated start of the scheduled ULtransmission.

FIG. 9 illustrates an example LBT type for scheduled UL transmission inFBE NR-U 900 according to embodiments of the present disclosure. Anembodiment of the LBT type for scheduled UL transmission in FBE NR-U 900shown in FIG. 9 is for illustration only. One or more of the componentsillustrated in FIG. 9 can be implemented in specialized circuitryconfigured to perform the noted functions or one or more of thecomponents can be implemented by one or more processors executinginstructions to perform the noted functions. Other embodiments are usedwithout departing from the scope of the present disclosure.

As illustrated in FIG. 9 , the LBT type for scheduled UL transmission isindicated by corresponding UL grant.

In one embodiment, the LBT type and/or LBT parameter for UL transmissioncan be semi-statically configured through higher layer parameter.

In one example, the higher layer parameter can configure the CAT-2 LBTas the default LBT type. In one sub-example, the CAT-2 LBT can refer tothe CAT-2 LBT type as in the mentioned embodiments and/or examples.

In one example, the higher layer parameter can configure a default CAT-2LBT type as one of the 16 μs CAT-2 LBT and 25 μs CAT-2 LBT when CAT-2LBT is used. In one sub-example, this example can be applied incombination with the mentioned embodiments and/or examples, wherein theCAT-2 LBT can be configured by DCI as the LBT type, the 16 μs CAT-2 LBTor 25 μs CAT-2 LBT can be configured by the higher layer parameter.

In one example, the higher layer parameter can configure the CAT-1 LBTas the default LBT type.

In one example, the higher layer parameter (e.g., RRC parameter)configured LBT type can be overridden by UL grant configured LBT typethrough dynamic indication.

In one embodiment, the LBT type and/or LBT parameter for UL transmissioncan be fixed by specification.

In one example, the fixed configuration of LBT type can be one of theCAT-1 LBT and CAT-2 LBT.

In one example, the fixed configuration of LBT type by specification canbe overridden by semi-static configuration through higher layerparameter or dynamic configuration through UL grant.

In one embodiment, the LBT type can be determined by the UE throughimplicit indication, wherein the UE can determine LBT type implicitly(i.e., without explicit LBT type field in the DCI) throughconfigurations by DCI and/or higher layer parameter.

In one example, the configurations by DCI and/or higher layer parameterthat can facilitate UE implicit derivation of LBT type can include theCOT duration and COT starting position, or the COT ending positioncorresponding to the COT wherein UL grant is received by the UE. In onesub-example, the COT starting position and COT duration, or the COTending position can be indicated through one or multiple of GC-PDCCH, UEspecific PDCCH, DM-RS, higher layer parameter(s). In anothersub-example, based on the gNB COT duration and/or the gNB COT endingposition, the UE can determine if the starting position of ULtransmission scheduled by the UL grant is within the current gNB COT ornot, and that CAT-1 LBT or CAT-2 LBT can be used if the startingposition of the scheduled UL transmission is inside the gNB COT, whereinthe specific LBT type (CAT-1 LBT, 16 μs CAT-2 LBT or 25 μs CAT-2 LBT)can be either indicated explicitly by DCI or derived implicitly by theUE through. For instance, CAT-1 LBT can be used if the gap between startof UL transmission and end of previous transmission within the COT iswithin 16 μs, and CAT-2 LBT otherwise.

In one example, the configurations by DCI and/or higher layer parameterthat can facilitate UE implicit derivation of LBT type can include thegNB COT structure, which configures the slot format for each slot withinthe gNB-initiated COT that contains the UL grant. In one sub-example,the COT structure can be obtained by the UE through group common(GC)-PDCCH. In another sub-example, the COT structure can be indicatedby the slot format indication (SFI) for each slot within the COT,wherein the SFI may indicate the symbol within a slot of the COT is DL,UL or flexible. In another sub-example, the UE can determine the gapduration from the end of the previous DL transmission within COT to thebeginning of a scheduled UL transmission based on the last DL symbolposition before the starting position of the scheduled UL transmission,which can be obtained through the gNB COT structure, as well as the ULTA value and/or starting position of the scheduled UL transmissionconfigured by DCI and/or higher layer parameter. For instance, CAT-1 LBTcan be used if the gap between start of UL transmission and end ofprevious transmission within the COT is within 16 μs, and CAT-2 LBTotherwise.

In one example, it can be up to UE implementation to decide the LBT type(e.g., 16/25 μs CAT-2 LBT, CAT-1 LBT) if a scheduled UL transmission ofUE can share the gNB-initiated COT containing the UL grant. In onesub-example, the UE can always use 25 μs as the baseline CAT-2 LBToption.

FIG. 10 illustrates another example LBT type for scheduled ULtransmission in FBE NR-U 1000 according to embodiments of the presentdisclosure. An embodiment of the LBT type for scheduled UL transmissionin FBE NR-U 1000 shown in FIG. 10 is for illustration only. One or moreof the components illustrated in FIG. 10 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

As illustrated in FIG. 10 , the UE can determine that a UL transmissionis within the current COT after detecting the GC-PDCCH, and the UE canchoose a corresponding UL LBT type according to the COT structureindicated in the GC-PDCCH.

In one embodiment, the scheduled UL transmission for FBE NR-U can berestricted to be contained within the same channel occupancy time of thefixed frame period that contains the UL grant which schedules the ULtransmission.

In one example, if a UE has received the UL grant, the UE can alwaysassume that a serving gNB has succeeded in the LBT to obtain the COT,and therefore the UE can transmit the scheduled UL transmission subjectto a successful LBT, which can be determined according to one of thementioned embodiments and/or examples.

In one example, this approach can be achieved by a gNB only choosingvalues in pusch-TimeDomainAllocationList in the UL grant that can ensurethe UL transmission is contained within the current COT.

In one example, if the scheduled UL transmission starts outside thecurrent COT that contains the UL grant, the UE can discard the ULtransmission.

In one example, if the scheduled UL transmission is not fully containedwithin the current COT that contains the UL grant (e.g., partiallycontained in the idle period), the scheduled PUSCH that falls outsidethe current COT can be punctured.

In one embodiment, the UL transmission for FBE NR-U can be allowed to bescheduled outside the same channel occupancy time of the fixed frameperiod that contains the UL grant which schedules the UL transmission.

In one example, if a UE has received the UL grant, the UE can start thescheduled UL transmission if the scheduled UL transmission is within agNB-obtained COT, and that the UE has succeed in the LBT according tothe LBT type determined from one of the mentioned embodiments and/orexamples. In one sub-example, the UE can determine if the scheduled ULtransmission is within a gNB-obtained COT, or equivalently if a servinggNB has succeeded in LBT to obtain the COT of the FFP wherein thescheduled UL transmission takes place, according to detecting if theserving gNB has transmitted group-common PDCCH (GC-PDCCH) to inform theUEs associated with a gNB about the following transmissions on the COT(which implicitly indicates the gNB has passed LBT in obtaining theCOT).

FIG. 11 illustrates yet another example LBT type for scheduled ULtransmission in FBE NR-U 1100 according to embodiments of the presentdisclosure. An embodiment of the LBT type for scheduled UL transmissionin FBE NR-U 1100 shown in FIG. 11 is for illustration only. One or moreof the components illustrated in FIG. 11 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

As illustrated in FIG. 11 , the UL grant schedules an UL transmission inthe next FFP (i.e., FFP1) that follows the COT/FFP (i.e., FFP0) whichcontains the UL grant; and the gNB has passed the CAT-2 LBT for FFP1 andhave correspondingly transmitted the GC-PDCCH, which has been detectedby the UE. Therefore, the UE can transmit the scheduled PUSCH after theUE has passed the LBT of type indicated by the UL grant or determined bythe UE.

In one example, if the scheduled UL transmission is within an FFPwherein the gNB failed LBT to obtain the corresponding LBT, the UE candiscard the scheduled UL transmission.

FIG. 12 illustrates yet another example LBT type for scheduled ULtransmission in FBE NR-U 1200 according to embodiments of the presentdisclosure. An embodiment of the LBT type for scheduled UL transmissionin FBE NR-U 1200 shown in FIG. 12 is for illustration only. One or moreof the components illustrated in FIG. 12 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

As illustrated in FIG. 12 , the gNB has failed the CAT-2 LBT to obtainthe FFP that follows the FFP containing the UL grant, therefore the UEmay discard the scheduled UL transmission which is scheduled within theFFP wherein the gNB has failed LBT.

In one example, if the scheduled UL transmission is within an FFPwherein the gNB failed LBT to obtain the corresponding LBT, the UE cantransmit the UL transmission if a CAT-2 LBT performed immediately beforethe scheduled UL transmission. In one sub-example, this example can beapplied regardless of the relative time position of the scheduled ULtransmission. In another sub-example, this example can be applied whenan FBE NR-U UE can be the initiating device to initiate a COT, whereinan FFP can be configured for the UE and the UL transmission can bescheduled to be at the beginning of the UE-associated FFP.

In one instance, the UE-associated FFP can be applied with the gNB FFP.In another instance, the UE-associated FFP can be different from thegNB-associated FFP. In another instance, the scheduled UL transmissioncan only start at the beginning of a UE-associated FFP, such that thestarting positions for scheduled PUSCH transmission has a granularity ofone UE-associated FFP. For example, the gNB can choose appropriate ULgrant to PUSCH delay to ensure this. In another example, the UE caninitiate the UL transmission in the earliest UE-associated FFP thatcomes no earlier than the scheduled starting position by the UL grant.In another instance, the UL grant to PUSCH delay (i.e., K2) can beinterpreted with a time-domain granularity of a UE-associated FFP. Forexample, K2=1 indicates the scheduled PUSCH starts at the beginning ofthe next UE-associated FFP, and a UE needs to pass a CAT-2 LBT beforethe start of the UE-associated FFP to transmit the scheduled PUSCH.

In another sub-example, this example can be applied when an FBE NR-U UEcan be the initiating device to initiate a COT, wherein an FFP can beconfigured for the UE and the scheduled UL transmission can be in themiddle of the UE-associated FFP and follows other UE UL transmissionsthat start at the beginning of the UE-initiated COT (e.g., CG-PUSCH orRACH). In one instance, the gap between the scheduled UL transmissionand the other UE UL transmissions that start at the beginning of theUE-initiated COT can be at most 16 μs. In another instance, the gapbetween the scheduled UL transmission and the other UE UL transmissionsthat start at the beginning of the UE-initiated COT can be more than 16μs, and the UE needs to pass a CAT-2 LBT before the scheduled ULtransmission to transmit the scheduled UL transmission.

In one example, if the scheduled UL transmission is not fully containedwithin the current COT that contains the UL grant (e.g., partiallycontained in the idle period), the scheduled PUSCH that falls outsidethe current COT can be punctured.

In one embodiment, enhancements for an FBE NR-U UE detection ofgNB-obtained COT is provided. In such embodiment, FBE NR-U UEs areprovided to detect if uplink transmission (whether dynamicallyscheduled, semi-statically configured or semi-persistently configured)is within a gNB-initiated COT.

In one embodiment, the FBE NR-U UE can determine if a serving gNB hasobtained the COT of current FFP through monitoring and detecting forGC-PDCCH.

In one example, the GC-PDCCH can be same as Rel-15 NR GC-PDCCH, whichrefer to a Type3-PDCCH common search space (CSS) set configured bySearchSpace in PDCCH-Config with searchSpaceType=common for DCI formatswith CRC scrambled by INT-RNTI, SFI-RNTI, TPC-PUSCH-RNTI,TPC-PUCCH-RNTI, or TPC-SRS-RNTI and, only for the primary cell, C-RNTI,MCS-C-RNTI, or CS-RNTI(s).

In one example, the GC-PDCCH can be enhanced from the Rel-15 NRGC-PDCCH, which can further indicate information such as the COTduration/ending time, valid LBT bandwidths that have passed LBT, etc.;and the GC-PDCCH can use a DCI format with CRC scrambled by one of theexisting RNTI(s) for GC-PDCCH from NR standard specification; or byintroducing a new RNTI for GC-PDCCH for NR-U.

In one example, the UE can determine that a serving gNB has obtained theCOT of the current FFP if the UE has detected GC-PDCCH from the gNB.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_CONNECTED FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_INACTIVE FBE NR-U UE.

In one embodiment, the FBE NR-U UE can determine if a serving gNB hasobtained the COT of current FFP through monitoring and detecting forUE-specific UL grant.

In one example, the UE can determine that a serving gNB has obtained theCOT of the current FFP if the UE has detected the UE-specific UL grantwith CRC scrambled by C-RNTI, MCS-C-RNTI, SP-CSI-RNTI, or CS-RNTI.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_CONNECTED FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_INACTIVE FBE NR-U UE.

In one embodiment, the FBE NR-U UE can determine if a serving gNB hasobtained the COT of current FFP through monitoring and detecting forPDCCH CSS set configured by MIB or by higher layer parameterPDCCH-ConfigCommon in SIB1/RMSI.

In one example, the UE can determine that a serving gNB has obtained theCOT of the current FFP if the UE has detected the cell-specific PDCCHfrom a serving gNB with the DCI format scrambled by a SI-RNTI.

In one example, the UE can determine that a serving gNB has obtained theCOT of the current FFP if the UE has detected the cell-specific PDCCHfrom a serving gNB with the DCI format scrambled by a P-RNTI.

In one example, the UE can determine that a serving gNB has obtained theCOT of the current FFP if the UE has detected the UE-specific UL grantwith CRC scrambled by C-RNTI, MCS-C-RNTI, SP-CSI-RNTI, or CS-RNTI.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_CONNECTED FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_INACTIVE FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_IDLE FBE NR-U UE.

In one embodiment, the FBE NR-U UE can determine if a serving gNB hasobtained the COT of current FFP through monitoring and detecting for theexistence of SS/PBCH and/or discovery reference sign (DRS) from aserving gNB.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_CONNECTED FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_INACTIVE FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_IDLE FBE NR-U UE.

In one embodiment, the UE FBE NR-U can determine if a serving gNB hasobtained the COT of current FFP through monitoring and detecting for theexistence of SIB1 and/or other system information (OSI) from a servinggNB.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_CONNECTED FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_INACTIVE FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_IDLE FBE NR-U UE.

In one embodiment, the FBE NR-U UE can determine if a serving gNB hasobtained the COT of current FFP through monitoring and detecting for thepaging message, which is scheduled by a PDCCH with a CSS setcorresponding to the serving gNB of UE and for a DCI format with CRCscrambled by a P-RNTI.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_CONNECTED FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_INACTIVE FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_IDLE FBE NR-U UE. For instance, this can be applied for IDLE UEsattempting PRACH transmission.

In one embodiment, the FBE NR-U UE can determine if a serving gNB hasobtained the COT of current FFP through monitoring and detecting for theshort messages transmitted on PDCCH using P-RTNI with or withoutassociated paging messages using short message field in DCI format 1_0.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_CONNECTED FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_INACTIVE FBE NR-U UE.

In one example, the mentioned examples and/or embodiments can be appliedto RRC_IDLE FBE NR-U UE. For instance, this can be applied for IDLE UEsattempting PRACH transmission.

In one example, the short message can include the cell-ID, based onwhich the UE can determine the short message corresponds to a servinggNB. In one sub-example, the short message field can be increased from 8bits to 10 bits for indicating the cell-ID.

In one embodiment, the FBE NR-U UE can determine the FFP duration andstarting position for each FFP associated with a serving gNB fromcorresponding configuration in RMSI.

In one embodiment, enhancements to support configured-grant ULtransmissions for FBE NR-U is provided. In such embodiment, thesignaling and indication methods are provided to support configuredgrant UL transmissions for FBE NR-U.

In one embodiment, the FBE NR-U can support configured grant uplinktransmissions.

In one example, both type 1 configured grant (i.e., semi-staticallyconfigured by higher layer parameters) and type 2 configured grant(i.e., semi-persistently scheduled by an UL grant in a validactivation/deactivation DCI) uplink transmissions can be supported byFBE NR-U.

In another example, only type 1 configured grant (i.e., semi-staticallyconfigured by higher layer parameters) uplink transmissions can besupported by FBE NR-U.

In yet another example, only type 2 configured grant (i.e.,semi-persistently scheduled by an UL grant in a validactivation/deactivation DCI) uplink transmissions can be supported byFBE NR-U.

In one embodiment, the FBE NR-U UE can be initiating device to initiatetransmission.

In one example, an explicit signaling from higher layer parameter (e.g.,RRC parameter) can be utilized to enable/disable the FBE UE as aninitiating device for transmission. In one sub-example, the FBE UEcannot be an initiating device for FBE transmission if the higher layerparameter disables the FBE UE to be the initiating device.

In another sub-example, the FBE UE can be an initiating device for FBEtransmission only if the higher layer parameter enables the FBE UE to bethe initiating device.

In one example, an explicit L1 signaling (e.g., from DCI) can beutilized to dynamically enable/disable the FBE UE as an initiatingdevice for transmission. In one sub-example, the FBE UE cannot be aninitiating device for FBE transmission if the L1 signaling disables theFBE UE to be the initiating device. In another sub-example, the FBE UEcan be an initiating device for FBE transmission only if L1 signalingenables the FBE UE to be the initiating device.

In another example, a MAC CE can be utilized to enable/disable the FBEUE as an initiating device for transmission. In one sub-example, the FBEUE cannot be an initiating device for FBE transmission if the MAC CEdisables the FBE UE to be the initiating device. In another sub-example,the FBE UE can be an initiating device for FBE transmission only if theMAC CE enables the FBE UE to be the initiating device.

In one example, the FBE NR-U UE can be an initiating device fortransmission only if the FBE NR-U UE determines a serving gNB has notobtained the COT associated with current FFP of the gNB. In onesub-example, the FBE NR-U UE can determine if a serving gNB has obtainedthe COT.

In one example, the FBE NR-U UE can be an initiating device fortransmission only if the FBE NR-U UE has non-scheduled UL transmissionconfigured to transmit within current FFP. In one sub-example, thenon-scheduled UL transmission can be all or a subset of theconfigured-grant PUSCH, PRACH, SRS. In another sub-example, the currentFFP can refer to the FFP associated with the gNB. In anothersub-example, the current FFP can refer to the FFP associated with theUE.

In one example, the FBE NR-U UE can be an initiating device fortransmission only if the FBE NR-U UE has scheduled UL transmissionconfigured to transmit within current FFP. In one sub-example, thecurrent FFP can refer to the FFP associated with the gNB. In anothersub-example, the current FFP can refer to the FFP associated with theUE.

In one example, an FBE NR-U UE can be an initiating device fortransmission if and only if one or multiple of the mentioned examplesand/or embodiments are met. In one sub-example, the FBE NR-U UE can bean initiating device if and only if the mentioned examples and/orembodiments are met.

In one example, when a UE is the initiating device for FBEtransmissions, the COT duration and/or the FFP duration associated withthe UE can be configured by one of semi-static configuration throughhigher layer parameter, and/or dynamic indication through layer 1 (L1)signaling and activation/de-activation by MAC CE, subject to regulationallowance. In one sub-example, the COT duration and/or the FFP durationassociated with an FBE NR-U UE can be explicitly configured withdedicated higher layer parameter, and/or MAC CE, and/or DCI formatand/or DCI field. In another sub-example, the COT duration and/or theFFP duration associated with the FBE NR-U UE can be implicitlyconfigured or implicitly inferred from other existing higher layerparameter, and/or MAC CE, and/or DCI format and/or DCI field. Forinstance, the COT duration and/or FFP duration associated with an NR-UUE can be same as that associated with the gNB.

In one example, when a UE is the initiating device for FBEtransmissions, the starting position of the FFP associated with the FBENR-U UE can be configured by one of semi-static configuration throughhigher layer parameter, and/or dynamic indication through layer 1 (L1)signaling and activation/de-activation by MAC CE. In one sub-example,the starting position of the FFP associated with the FBE NR-U UE can beexplicitly configured with dedicated higher layer parameter, and/or MACCE, and/or DCI format and/or DCI field. In another sub-example, thestarting position of the FFP associated with the FBE NR-U UE can beimplicitly configured or implicitly inferred from other existing higherlayer parameter, and/or MAC CE, and/or DCI format and/or DCI field.

In one embodiment, the FBE NR-U UE can transmit in the configured grant(CG) PUSCH occasion only through sharing a valid gNB-initiated COTwherein the UE can determine or can be informed that a serving gNB hasobtained COT that contains the configured CG PUSCH occasion, and thatthe UE has passed LBT corresponding to the CG PUSCH occasion.

In one example, the FBE NR-U can determine if a CG PUSCH occasion iswithin a gNB-initiated COT by following one of examples and/orembodiments.

In one example, the LBT type can be fixed to be CAT-2 LBT.

In one example, the LBT type can be implicitly determined by the UEaccording to the mentioned examples and/or embodiments.

In one example, the LBT type for CG PUSCH occasion with type 2 CG-PUSCHcan be indicated through the PDCCH that is used foractivating/de-activating the type-2 CG. In one sub-example, additionalfield to indicate the LBT type can be introduced for the correspondingDCI format used to activate/de-activate the type-2 configured UL grant,which can be achieved according to the mentioned examples and/orembodiments.

FIG. 13 illustrates yet another example LBT type for scheduled ULtransmission in FBE NR-U 1300 according to embodiments of the presentdisclosure. An embodiment of the LBT type for scheduled UL transmissionin FBE NR-U 1300 shown in FIG. 13 is for illustration only. One or moreof the components illustrated in FIG. 13 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

As illustrated in FIG. 13 , the UE can determine CG-PUSCH occasions arewithin a gNB-initiated COT by detecting the GC-PDCCH, and the UE canutilize the CG-PUSCH occasions when LBT for CG-PUSCH has passed.

In one embodiment, the FBE NR-U UE can be the initiating device and hasan associated COT and/or FFP, such that the FBE NR-U UE transmit in theconfigured grant (CG) PUSCH occasion if a UE has passed the LBTcorresponding to the FFP associated with the UE that contains theCG-PUSCH occasion.

In one example, the COT duration and/or the FFP duration associated withthe UE can be configured by one of semi-static configuration throughhigher layer parameter, and/or dynamic indication through layer 1 (L1)signaling and activation/de-activation by MAC CE, subject to regulationallowance. In one sub-example, the COT duration and/or the FFP durationassociated with an FBE NR-U UE can be explicitly configured withdedicated higher layer parameter, and/or MAC CE, and/or DCI formatand/or DCI field.

In another sub-example, the COT duration and/or the FFP durationassociated with an FBE NR-U UE can be implicitly configured orimplicitly inferred from other existing higher layer parameter, and/orMAC CE, and/or DCI format and/or DCI field. For instance, the FFPduration can be the minimum of the periodicity of the configured granttype 1 or type 2, and the maximum FFP duration allowed by the regulation(e.g., 10 ms).

In one example, the CG-PUSCH can be at the beginning of the of the FFPassociated with the UE, such that the CG-PUSCH can be transmitted oncethe UE has passed LBT corresponding to the FFP/COT wherein the CG-PUSCHis configured.

In one example, the CG-PUSCH can be in the middle of the of the FFPassociated with the UE, and such CG-PUSCH can be transmitted if the UEhas passed LBT corresponding to the FFP/COT wherein the CG-PUSCH isconfigured; and that: if there is a gap duration larger than 16 μs withrespect to the end of the previous transmission in the COT before theconfigured CG-PUSCH, the UE has passed a CAT-2 LBT before the CG-PUSCHin the middle of the of the FFP, as illustrated in FIG. 14 . FIG. 14illustrates an example CG-PUSCH for an FBE UE 1400 according toembodiments of the present disclosure. An embodiment of the CG-PUSCH foran FBE UE 1400 shown in FIG. 14 is for illustration only. One or more ofthe components illustrated in FIG. 14 can be implemented in specializedcircuitry configured to perform the noted functions or one or more ofthe components can be implemented by one or more processors executinginstructions to perform the noted functions. Other embodiments are usedwithout departing from the scope of the present disclosure.

If a gap duration is at most 16 μs with respect to the end of theprevious transmission in the COT before the configured CG-PUSCH, the UEcan directly transmit the CG-PUSCH in the middle of the of the FFP, asillustrated in FIG. 15 .

FIG. 15 illustrates another example CG-PUSCH for an FBE UE 1500according to embodiments of the present disclosure. An embodiment of theCG-PUSCH for an FBE UE 1500 shown in FIG. 15 is for illustration only.One or more of the components illustrated in FIG. 15 can be implementedin specialized circuitry configured to perform the noted functions orone or more of the components can be implemented by one or moreprocessors executing instructions to perform the noted functions. Otherembodiments are used without departing from the scope of the presentdisclosure.

In one example, the FFP duration and/or the COT duration associated withthe UE can be fixed in the specification.

In one example, the FFP duration and/or the COT duration associated withthe UE can be the same as that of the periodicity for configured granttransmission. In one sub-example, the CG-PUSCH can be at the beginningof the of the FFP associated with the UE, such that the CG-PUSCH can betransmitted once the UE has passed LBT corresponding to the FFP/COTwherein the CG-PUSCH is configured.

FIG. 16 illustrates yet another example CG-PUSCH for an FBE UE 1600according to embodiments of the present disclosure. An embodiment of theCG-PUSCH for an FBE UE 1600 shown in FIG. 16 is for illustration only.One or more of the components illustrated in FIG. 16 can be implementedin specialized circuitry configured to perform the noted functions orone or more of the components can be implemented by one or moreprocessors executing instructions to perform the noted functions. Otherembodiments are used without departing from the scope of the presentdisclosure.

As illustrated in FIG. 16 , a configured grant type 1 is used.

FIG. 17 illustrates yet another example CG-PUSCH for an FBE UE 1700according to embodiments of the present disclosure. An embodiment of theCG-PUSCH for an FBE UE 1700 shown in FIG. 17 is for illustration only.One or more of the components illustrated in FIG. 17 can be implementedin specialized circuitry configured to perform the noted functions orone or more of the components can be implemented by one or moreprocessors executing instructions to perform the noted functions. Otherembodiments are used without departing from the scope of the presentdisclosure.

As illustrated in FIG. 17 , a configured grant type 2 is used and the UEcan transmit in CG-PUSCH if CG-PUSCH is activated in a FFP and the UEhas passed LBT; and the UE does not need to perform LBT if CG-PUSCH isde-activated in a FFP.

In one example, the periodicity for configured grant transmission can bean integer multiple of the FFP duration and/or the COT durationassociated with the UE. In one sub-example, the CG-PUSCH can be at thebeginning of the of the FFP associated with the UE, such that theCG-PUSCH can be transmitted once the UE has passed LBT corresponding tothe FFP/COT wherein the CG-PUSCH is configured.

As illustrated in FIG. 17 , the UE can transmit in CG-PUSCH if CG-PUSCHis activated in a FFP and the UE has passed LBT; and the UE does notneed to perform LBT if CG-PUSCH is de-activated in a FFP or the FFP doesnot contain a CG-PUSCH.

In one example, the FFP duration and/or the COT duration associated withthe UE can be an integer multiple of the periodicity for configuredgrant transmission. In one sub-example, the CG-PUSCH can be at thebeginning of the of the FFP associated with the UE, and such CG-PUSCH atthe beginning of the FFP can be transmitted once the UE has passed LBTcorresponding to the FFP/COT wherein the CG-PUSCH is configured. Inanother sub-example, the CG-PUSCH can be in the middle of the of the FFPassociated with the UE, and such CG-PUSCH can be transmitted if the UEhas passed LBT corresponding to the FFP/COT wherein the CG-PUSCH isconfigured; and that if there is a gap duration larger than 16 μs withrespect to the CG-PUSCH in the beginning of the FFP, the UE has passed aCAT-2 LBT before the CG-PUSCH in the middle of the of the FFP, asillustrated in FIG. 18 .

FIG. 18 illustrates yet another example CG-PUSCH for an FBE UE 1800according to embodiments of the present disclosure. An embodiment of theCG-PUSCH for an FBE UE 1800 shown in FIG. 18 is for illustration only.One or more of the components illustrated in FIG. 18 can be implementedin specialized circuitry configured to perform the noted functions orone or more of the components can be implemented by one or moreprocessors executing instructions to perform the noted functions. Otherembodiments are used without departing from the scope of the presentdisclosure.

In one example, the FFP duration and/or the COT duration associated withthe UE do not need to start with a CG-PUSCH at the beginning of the FFPduration and/or the COT duration. In one sub-example, this can happenwhen (periodicity of CG-PUSCH/FFP=m/n) with m and n both being integervalues. In another sub-example, this can be applied when different FBEUEs are utilizing a synchronized FFP.

In one example, the mentioned examples and/or embodiments can be usedonly if the gNB has failed LBT corresponding to obtain the COTassociated with the gNB that contains the CG-PUSCH; or the mentionedembodiments and/or examples can always be utilized by the UE to transmitCG-PUSCH irrespective if the gNB has obtained the COT or not.

In one example, the mentioned embodiments and/or examples can be appliedto other periodic uplink transmission such as the periodic soundingreference signal (SRS) for FBE NR-U in addition to CG-PUSCH.

In one embodiment, enhancements to support PRACH transmissions for FBENR-U is provided. In such embodiment, enhancement of the FBE NR-U isprovided to support PRACH transmissions.

In one embodiment, the FBE NR-U can support PRACH transmissions by theUE.

In one example, the IDLE UE can transmit PRACH which is configured byhigher layer parameters.

In one example, the UE can also transmit PRACH scheduled through PDCCHorder or DCI.

In one example, the UE can also transmit PRACH that follows the DRS.

In one embodiment, the FBE NR-U UE can transmit PRACH only throughsharing a valid gNB-initiated COT wherein the UE can determine or can beinformed that a serving gNB has obtained COT that contains theUE-associated RACH occasion (RO), and that the UE has passed LBTcorresponding to the RO.

In one example, the FBE NR-U can determine if a CG PUSCH occasion iswithin a gNB-initiated COT by following one of examples and/orembodiment.

In one example, the LBT type can be fixed to be CAT-2 LBT.

In one example, the LBT type can be implicitly determined by the UEaccording to the mentioned embodiments and/or examples.

In one example, the LBT type can be explicitly indicated to the UEaccording through PDCCH order or other DCI formats.

In one embodiment, the FBE NR-U UE can be the initiating device and hasan associated COT and/or FFP, such that the FBE NR-U UE transmit in theconfigured valid RACH occasion if the UE has passed the LBTcorresponding to the FFP associated with the UE that contains the RACHoccasion.

In one example, the COT duration and/or the FFP duration associated withthe UE can be configured by one of semi-static configuration throughhigher layer parameter, and/or dynamic indication through layer 1 (L1)signaling and activation/de-activation by MAC CE, subject to regulationallowance.

In one sub-example, the COT duration and/or the FFP duration associatedwith an FBE NR-U UE can be explicitly configured with dedicated higherlayer parameter, and/or MAC CE, and/or DCI format and/or DCI field.

In another sub-example, the COT duration and/or the FFP durationassociated with an FBE NR-U UE can be implicitly configured orimplicitly inferred from other existing higher layer parameter, and/orMAC CE, and/or DCI format and/or DCI field. For instance, the FFPduration can be the minimum of the PRACH configuration period, and themaximum FFP duration allowed by the regulation (e.g., 10 ms).

In one example, the FFP duration and/or the COT duration associated withthe UE can be fixed in the specification. For instance, since the PRACHconfiguration period is an integer multiple of 10 ms, the FFP durationcan be set as 10 ms.

In one example, an RO can be at the beginning of the of the FFPassociated with the UE, such that the PRACH can be transmitted once theUE has passed LBT corresponding to the FFP/COT wherein the RO isconfigured.

In one example, an RO can be in the middle of the COT/FFP associatedwith the UE, and the UE can transmit PRACH if the UE has passed LBTcorresponding to the FFP/COT wherein the RO is configured; and that: ifthere is a gap duration larger than 16 μs with respect to the end of theprevious transmission in the COT before the configured RO, and the UEhas passed a CAT-2 LBT before the RO; or if there is a gap duration ofat most 16 μs with respect to the end of the previous transmission inthe COT before the configured RO, the UE can directly transmit the PRACHin the configured RO.

In one example, the FFP duration and/or the COT duration associated withthe UE can be the same as that of the PRACH configuration period. In onesub-example, this condition happens when both the PRACH configurationperiod and UE FFP are 10 ms.

FIG. 19 illustrates an example RO for an FBE UE 1900 according toembodiments of the present disclosure. An embodiment of the RO for anFBE UE 1900 shown in FIG. 19 is for illustration only. One or more ofthe components illustrated in FIG. 19 can be implemented in specializedcircuitry configured to perform the noted functions or one or more ofthe components can be implemented by one or more processors executinginstructions to perform the noted functions. Other embodiments are usedwithout departing from the scope of the present disclosure.

As illustrated in FIG. 19 , two ROs (not evenly distributed within theCOT/FFP) are configured for an FBE UE within an FFP, wherein the FFP issame as the PRACH configuration period.

In one example, the UE-configured RO positions can repeat in a periodicpattern wherein the pattern periodicity can be an integer multiple ofthe FFP duration associated with the UE. In one sub-example, suchperiodic pattern can have the periodicity of the PRACH configurationperiod, or association period between SSB and RO, or association patternperiod between the SSB and RO.

In one embodiment, the RACH occasion validation rule can be enhancedfrom Rel-15 NR, such that RO that overlaps with IDLE period of the FBEfixed frame period can be considered as invalid.

In one example, the FBE FFP can be the FFP associated with the FBE NR-UgNB. In one sub-example, this can be applied when the mentionedembodiments and/or examples are used, such that the UE can transmit ROby only sharing gNB-initiated COT.

In one example, the FBE FFP can be the FFP associated with the FBE NR-UUE. In one sub-example, this can be applied when the UE can transmitPRACH through UE-initiated COT wherein the UE is the initiating device.

In one example, the FBE NR-U has PRACH validation rule as follows: if aUE is provided TDD-UL-DL-ConfigurationCommon, a PRACH occasion in aPRACH slot is valid if the RO does not overlap with the IDLE period ofthe FFP of the initiating device to transmit PRACH, and: the PRACHoccasion is within UL symbols, or the PRACH occasion does not precede aSS/PBCH block in the PRACH slot and starts at least gap N symbols aftera last downlink symbol and at least gap N symbols after a last SS/PBCHblock transmission symbol, where gap N is fixed in spec or configured byhigher layer parameter or DCI.

FIG. 20 illustrates a flow chart of a method 2000 for uplinktransmission in frame-based equipment NR unlicensed according toembodiments of the present disclosure, as may be performed by a userequipment (e.g., 111-116 as illustrated in FIG. 1 ). An embodiment ofthe method 2000 shown in FIG. 20 is for illustration only. One or moreof the components illustrated in FIG. 20 can be implemented inspecialized circuitry configured to perform the noted functions or oneor more of the components can be implemented by one or more processorsexecuting instructions to perform the noted functions. Other embodimentsare used without departing from the scope of the present disclosure.

As illustrated in FIG. 20 , the method 2000 begins at step 2002. In step2002, the UE in a wireless communication system supporting a sharedspectrum channel access receives, from a base station (BS) over a sharedspectrum channel, a first downlink control information (DCI) including achannel occupancy time (COT) of the BS.

Subsequently, the UE in step 2004 determines a first portion of the COTfor a downlink transmission from the BS and a second portion of the COTfor an uplink transmission to the BS, wherein the COT includes a gapbetween the first and second portions of the COT.

Subsequently, the UE in step 2006 performs a channel access procedurebased on a duration of the gap.

In one embodiment, the channel access procedure does not include a timeduration for sensing the shared spectrum channel, the duration of thegap being no longer than 16 microseconds.

In one embodiment, the channel access procedure includes a time durationof 16 microseconds for sensing the shared spectrum channel, the durationof the gap being longer than 16 microseconds.

Next, the UE in step 2008 receives, from the BS over the shared spectrumchannel, the downlink transmission in the first portion of the COT.

Finally, the UE in step 2010 transmits, to the BS over the sharedspectrum channel, the uplink transmission in the second portion of theCOT based on a sensing status of the shared spectrum channel that issensed as an idle state during the channel access procedure in theduration of the gap.

In one embodiment, the UE identifies an operation mode of the BS and,based on identifying that the operation mode of the BS is a semi-staticmode, further identifies that a period exists before starting the COTduring which transmissions are not allowed.

In one embodiment, the UE determines that a physical random accesschannel (PRACH) occasion is valid, wherein the PRACH occasion does notoverlap with a period before starting the COT during which transmissionsare not allowed.

In one embodiment, the UE determines a second DCI from the downlinktransmission included in the first portion of the COT.

In such embodiment, the second DCI includes a type of channel accessoperation for the uplink transmission included in the second portion ofthe COT; and the type of channel access operation is one of: a type ofchannel access procedure not including a time duration for sensing theshared spectrum channel, or a type of channel access procedure includinga time duration of 16 microseconds for sensing the shared spectrumchannel.

Although the present disclosure has been described with an exemplaryembodiment, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims. None of the description in this application should be read asimplying that any particular element, step, or function is an essentialelement that must be included in the claims scope. The scope of patentedsubject matter is defined by the claims.

What is claimed is:
 1. A method performed by a user equipment (UE)operating in a shared spectrum channel, the method comprising:receiving, from a base station, a downlink (DL) transmission in achannel occupancy time (COT); identifying a time gap between the DLtransmission and an uplink (UL) transmission; identifying whether toperform a channel sensing before the UL transmission according to avalue of the time gap; and transmitting, to the base station, the ULtransmission within the COT, wherein a maximum of the COT Ty isidentified as Ty=0.95Tx, where Tx is a duration configured by a higherlayer parameter.
 2. The method of claim 1, wherein: a channel occupancyassociated with the COT is initiated by the base station, and the ULtransmission of the UE is transmitted based on a detection of the DLtransmission within the COT.
 3. The method of claim 1, wherein the ULtransmission is transmitted within the COT without the channel sensingin case that the value of the time gap is at most 16 μs.
 4. The methodof claim 1, wherein the UL transmission is transmitted within the COTafter the channel sensing in case that the value of the time gap is morethan 16 μs and the channel is identified to be idle for at least asensing slot duration within a 25 μs interval before the ULtransmission.
 5. The method of claim 4, wherein the sensing slotduration equals 9 μs.
 6. The method of claim 1, wherein physical randomaccess channel (PRACH) occasion is identified to be valid based onwhether the PRACH occasion overlaps with a time period before a start ofthe COT.
 7. The method of claim 6, wherein the time period is associatedwith a duration of the COT.
 8. A user equipment (UE), comprising: atransceiver configured to receive, from a base station, a downlink (DL)transmission in a channel occupancy time (COT); and a processor operablycoupled to the transceiver, the processor configured to: identify a timegap between the DL transmission and an uplink (UL) transmission; andidentify whether to perform a channel sensing on a channel before the ULtransmission according to a value of the time gap, wherein thetransceiver is configured to transmit, to the base station, the ULtransmission within the COT, and wherein a maximum of the COT Ty isidentified as Ty=0.95Tx, where Tx is a duration configured by a higherlayer parameter.
 9. The UE of claim 8, wherein: a channel occupancyassociated with the COT is initiated by the base station, and the ULtransmission of the UE is transmitted based on a detection of the DLtransmission within the COT.
 10. The UE of claim 8, wherein the ULtransmission is transmitted within the COT without the channel sensingin case that the value of the time gap is at most 16 μs.
 11. The UE ofclaim 8, wherein the UL transmission is transmitted within the COT afterthe channel sensing in case that the value of the time gap is more than16 μs and the channel is identified to be idle for at least a sensingslot duration within a 25 μs interval before the UL transmission. 12.The UE of claim 11, wherein the sensing slot duration equals 9 μs. 13.The UE of claim 8, wherein physical random access channel (PRACH)occasion is identified to be valid based on whether the PRACH occasionoverlaps with a time period before a start of the COT.
 14. The UE ofclaim 13, wherein the time period is associated with a duration of theCOT.
 15. A base station, comprising: a transceiver configured toreceive, from a user equipment (UE), an uplink (UL) transmission in achannel occupancy time (COT); and a processor operably coupled to thetransceiver, the processor configured to: identify a time gap betweenthe UL transmission and a downlink (DL) transmission; and identifywhether to perform a channel sensing on a channel before the DLtransmission according to a value of the time gap, wherein thetransceiver is configured to transmit, to the UE, the DL transmissionwithin the COT, and wherein a maximum of the COT Ty is identified asTy=0.95Tx, where Tx is a duration configured by a higher layerparameter.
 16. The base station of claim 15, wherein: a channeloccupancy associated with the COT is initiated by the base station, andthe DL transmission of the base station is transmitted based on adetection of the UL transmission within the COT.
 17. The base station ofclaim 15, wherein the DL transmission is transmitted within the COTwithout the channel sensing in case that the value of the time gap is atmost 16 μs.
 18. The base station of claim 15, wherein the DLtransmission is transmitted within the COT after the channel sensing incase that the value of the time gap is more than 16 μs and the channelis identified to be idle for at least a sensing slot duration.
 19. Thebase station of claim 18, wherein the sensing slot duration equals 9 μs.20. The base station of claim 15, wherein physical random access channel(PRACH) occasion is identified to be valid based on whether the PRACHoccasion overlaps with a time period before a start of the COT.